Such methods, controllers and networks are substantially known in the art; in particular they are known for universal mobile telecommunications systems UMTS-technology
In the European patent application 1 202 586 A1 the basic concept of a UMTS-Radio Network is described. In a minimum configuration such a Radio Network comprises at least one terminal, at least one base station, at least one Radio Network Controller and finally at least one exchange. The Radio Network Controller RNC controls all cells in a rather large geographical area. For signaling between the terminals and the Radio Network Controller different protocols and in particular a Radio Resource Control Protocol has been defined. These protocols provide a standardized structure for the messages to be transferred in the way that these messages comprise a certain number of information fields for a predefined content. In the original UMTS Radio Access Network UTRAN architecture to identify a terminal, two parameters have been specified: the SRNC-ID, which identifies the serving RNC responsible for the user connection and the S-RNTI, which is an identifier for the user or terminal, generated by the serving RNC during the RRC establishment and unique within this serving RNC. In the same way, to identify a particular cell, two parameters have been specified: the CRNC-ID, which identifies the Controlling RNC, responsible for the control of a particular area, and the C-ID, which uniquely identifies a cell within the area controlled by the CRNC. Therefore, several messages whose internal structure has been standardized contain these fields which must be filled with the corresponding information.
However, in the meantime after the filing of the mentioned European patent application EP 1 202 586 A1, the architecture described therein has been evolved. In particular, the Radio Network Controller RNC has been split into several functional entities. Said evolved architecture is described in the not pre-published European patent application having the application number 02360168.5 and is illustrated in FIG. 4 of the present application. The functional entities shown there have different scopes for example a user scope i.e. there is one instance per connected user, a cell scope i.e. there is one instance per cell or a multi-cell scope i.e. there is one instance for a group of cells.
The functional entities relevant for the present description are the paging and broadcast P&B functional entity, a Cell Control CC functional entity and a Mobile Control MC functional entity. Hereinafter the term functional entity will typically be dropped for facilitating the following description.
The paging and broadcast P&B has a multi-cell scope. It is responsible, among other functions, to distribute paging messages used to locate a particular user in case of incoming calls and cell broadcast system messages used to send some kind of information, e.g. some short news service to all users in a cell onto which the messages should be sent.
The Cell Control has a cell scope. It is responsible for control functions related to a particular cell and it terminates the control channels associated with this cell such as a common control channel CCCH.
The Mobile Control has a user scope. It is dynamically instantiated that means created when a new signaling connection known as Radio Resource Control RRC connection is established for a particular user. It terminates the RRC connection and a Dedicated Control Channel DCCH for the user which is established by a RRC connection establishment.
As described later, a paging and broadcast functional entity is involved in the creation (instantiation) of a particular Mobile Control functional entity. From now on, this paging and broadcast functional entity will be referred to as the parent paging and broadcast PP&B of said Mobile Control.
As can be seen in FIG. 4, the Radio Access Network RAN and in particular the Radio Network Controller RNC is connected to a Core Network CN. For routing messages sent by a terminal/user UE on the CCCH of a particular cell between the Cell Control CC associated to the Base Station NB and the Mobile Control MC responsible for the user connection, the mentioned functional entities have to communicate with each other.
Starting from the prior art it is the object of the present invention to provide possible methods for routing a message from the Cell Control to a Mobile Control, and for routing a message from a Mobile Control to a Cell Control in such a manner that traditionally used protocols for routing such messages can be used without being changed. Further, it is the object of the invention to provide a distributed Radio Network Control RNC equipment and a Radio Access Network for carrying out said methods.